Clinical utility of two-dimensional magnetic resonance angiography in detecting coronary artery disease

AIMS: The accuracy of magnetic resonance angiography in detectingproximal coronary artery stenoses is unclear. We postulatedthat fast magnetic resonance angiography is capable of (1) imagingproximal coronary arteries, and (2) detecting stenoses of 50%of their luminal diameter. METHODS AND RESULTS: Thirty-five patients, referred for analysis of angina pectoris,underwent both conventional angiography and magnetic resonanceangiography of coronary arteries. A fast k-space segmented gradient-echotechnique was used during breath-holds. Two observers, blindedto the results of conventional angiography, independently analysedthe magnetic resonance studies for (1) length of visualizedsegments, and (2) presence of signal voids indicative of stenoses.From 140 proximal arteries, 15 (11%) were excluded because ofincomplete imaging or degraded image quality. Mean length ofthe visualized segments was 9±4 mm for the left main,62±16 mm for the left anterior descending, 21±9mm for the left circumflex and 89±32 mm for the rightcoronary artery. Sensitivity for detecting 50% luminal diameterstenoses was 0·00 for the left circumflex, 0·53for the left anterior descending coronary artery, 0·71for the RCA and 1·00 for the left main artery. Specificityvaried from 0·73 for the left anterior descending coronaryartery to 0·96 for the left circumflex. Inter-observeragreement was 0·90. CONCLUSION: Thus, segmented magnetic resonance angiography is capable ofnon-invasive imaging of proximal coronary anatomy. Its goodaccuracy in detecting left main coronary artery disease, intermediateaccuracy in detecting right coronary artery and left anteriordescending coronary artery stenoses, and low accuracy in detectingleft circumflex lesions fit within a range of sensitivitiesand specificities found by others. Further technical advancesare necessary to make the technique clinically robust.